In a known sunshade apparatus for a vehicle disclosed in U.S. Pat. No. 6,874,845 B2, a garnish attached to an end of the shading sheet is equipped with a leaf spring at both ends of the garnish for the purpose of adjusting a shading sheet to stay open at a desired position against the winding force of a retracting unit. According to the disclosure in U.S. Pat. No. 6,874,845 B2, a frictional force is produced by each leaf spring pressing against a corresponding guide rail and works against a biasing force in a retraction direction to maintain the opening state of the sunshade apparatus.
In another known sunshade apparatus for a vehicle disclosed in JP2000-272341A, a garnish and a retracting unit for winding a shading sheet are connected by wires for a purpose of reducing operational force. Winding directions of the wires and the shading sheet are opposite to each other in a manner so that when the shading sheet is wound off, a retracting unit winds in the wires in turn. Spring biased guide rollers provide tensional forces to the wires and the shading sheet to balance the tensional force on the wire and the tensional force on the shading sheet. According to the disclosure in JP2000-272341A, the shading sheet includes the garnish at the front end, and the garnish is supported in a manner to slide freely along guide rails intermediated by shoes.
According to the disclosure in U.S. Pat. No. 6,874,845 B2, a large operational force is required because a frictional force is constantly working to support the garnish.
According to the disclosure in JP2000-272341A, a downward slacking of the closed shading sheet easily occurs at the middle portion because the wires are retaining the shading sheet from the front end alone via the garnish.
A need thus exists for a sunshade apparatus for a vehicle which is not susceptible to the drawbacks mentioned above.